\ifcmh body of the environment body of the environment body of the environment \fi some more text

\ifcmh#1<2 body of the environment body of the environment body of the environment \fi % comment!

\ifodd\mynumber body of the environment body of the environment body of the environment \fi% comment!

here is some text \if x^2 \fi text

\if body %comment
\fi

\if% here's a comment
body
\else else body \fi
